Systems and methods relating to a corner block for a mattress

ABSTRACT

The invention, in various embodiments, is directed to devices, systems and methods relating to a corner block for a mattress.

FIELD OF THE INVENTION

The invention relates generally to mattresses. More particularly, in various embodiments, the invention relates to a corner block for providing a reinforced square corner on a mattress, mattresses made with such corner blocks, and methods of manufacturing mattresses employing such corner blocks.

BACKGROUND OF THE INVENTION

Conventionally, mattresses generally have unreinforced, rounded corners. When installed into a crib frame, conventional mattress corners make it possible for an infant to injure him/herself by lodging an extremity, such as an arm or leg, between the crib frame and the corner of the crib mattress.

Various prior art approaches have been employed to reduce the likelihood of this occurring. In some instances, crib bumpers are employed. Typically, crib bumpers are affixed along the periphery of a crib mattress and extend upward and between the mattress and the crib sides. A disadvantage to bumpers is that they often pull away from the corners of the mattress and leave a gap between a mattress corner and a corner of the crib frame. Another prior art approach employs mattresses that extend upward along their periphery to provide an integrated bumper. However, such mattresses can be significantly more complicated to manufacture.

Accordingly, there is a need for an improved structure for a crib mattress.

SUMMARY OF THE INVENTION

The invention addresses the deficiencies in the prior art by, in various embodiments, providing a corner block for squaring a corner of a mattress. In other embodiments, the invention provides mattresses employing the corner block of the invention and methods of manufacturing such mattresses. In some embodiments, a mattress of the invention may be employed as a crib mattress. An advantage of such crib mattresses is that they better fit within the corners of a crib frame to inhibit an infant from lodging an extremity between a corner of the mattress and a corner of the crib frame.

According to one aspect, the invention provides a corner block formed from a shape resilient polymer material, such as, polyurethane foam, visco-elastic foam, latex, polyethylene foam, polystyrene, or from cardboard, wood, metal, wire, plastic molded part, polypropylene, and acrylonitrile butadiene styrene (ABS). In one implementation, the polymer material has a density of about 23 kilograms/meter³. In other implementations, the polymer material has a density of between about 18 kilograms/meter³ and about 28 kilograms/meter³. In other implementations, the polymer material has a density of between about 20 kilograms/meter³ and about 26 kilograms/meter³. In other embodiments, the corner block of the invention may be formed from any suitable material depending on the desired application.

The corner block includes first and second legs, which extend from a vertex at an angle to each other. Each leg includes an inner (e.g., frame contacting) surface and an outer surface. In one configuration, the outer surfaces of the first and second legs intersect at a substantially right angle. In one embodiment, each leg is about 4½ inches long, as measured from the intersection of the outer surfaces of the first and second legs to terminal ends of each respective leg. According to a further embodiment, the first and second legs are about 4½ inches high. According to an alternative embodiment, each leg is about 5 inches high. In other configurations, the legs of the corner block are between about 4 inches and about 10 inches long and between about 4 inches and about 10 inches high. In alternate configurations, the legs of the corner block are between about 4 inches and about 6 inches long. In further configurations, the legs of the corner block are between about 4 inches and about 6 inches high.

According to another feature, the legs are between about ¼ inch and about 1½ inches thick as measured from the inner surface to the outer surface. In some embodiments, the outer surfaces of the first and second legs each include first and second sections. The first section of each leg extends from the vertex at approximately a right angle to each other, and the second section of each leg extends from a terminal end of a respective first section of each leg along an axis angled inward relative to a respective axis of the respective first section.

According to some configurations, the inner surfaces of the first and second legs intersect at a transition section. According to one feature, the transition section is sized and shaped to interfit around a corner of a coil spring mattress frame. According to another feature, the transition section may be curved to further facilitate such interfitting. In one embodiment, the distance between the vertex of the angle of intersection of the outer surfaces and the apex of the curve of the transition section is between about ¾ inch and about 1½ inches.

In some embodiments, a portion of the inner surfaces of the first and second legs may be carved out to receive a corner of a coil spring mattress frame. According to one feature of these embodiments, the carve out may be sized and shaped such that upper and lower parts of the legs may overlap upper and lower sides of a mattress frame, when interfitted onto a corner of the frame to facilitate attaching the corner block to the frame.

According to another aspect, the invention is directed to a mattress employing a corner block of the invention. In one embodiment, the mattress includes a coil spring frame, in which the coil springs may or may not be pocketed. The corner blocks are attached to each corner of the frame, either prior or subsequent to attachment of polymer foam material to short ends of the frame. The mattress of the invention may then be further assembled by any suitable approach. According various constructions, the mattress may be of any size, including without limitation, single, double, full, queen, king, California king, or crib size.

According to a further embodiment, subsequent to attachment of a fire retardant material, the mattress is placed in a compression bag. With the mattress so placed, the compression bag is evacuated to compress it, including compressing the coil springs of the mattress frame. With the mattress so compressed, it is inserted into a final mattress cover. The cover may then be closed by any suitable mechanism. Optionally, the compression bag may be removed prior to closing the mattress cover. In some instances, the compression bag may be made from a water resistant polymer and left on the mattress to shield inner portions of the mattress from inadvertent exposure to fluids during use.

Other features and advantages of the invention are described below with regard to various illustrative embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be better understood with reference to the appended illustrative drawings in which like reference designations refer to like parts, the various views may not be drawn to scale; and in which:

FIG. 1A is a top view of a corner block for providing a reinforced square corner on a mattress according to an illustrative embodiment of the invention;

FIG. 1B is an outside perspective view of the corner block of FIG. 1A;

FIG. 1C is an inside perspective view of the corner block of FIG. 1A;

FIG. 1D is an inside perspective view of the corner block of FIG. 1A including an optional cutout according to another illustrative embodiment of the invention;

FIGS. 2A-2H depict an illustrative process for making a mattress that includes a corner block of the invention;

FIG. 3 depicts an alternative embodiment of the invention; and

FIG. 4 depicts a further alternative embodiment of the invention.

ILLUSTRATIVE DESCRIPTION

As described above in summary, the invention addresses the deficiencies in the prior art by providing, in various illustrative embodiments, devices, systems and methods relating to forming a substantially square corner on a mattress. According to various implementations, the invention provides a corner block for attaching to an otherwise curved/rounded corner of a mattress frame. One advantage of the corner blocks of the invention is that they may be applied to the corners of conventional mattress frames, without need of changing the process by which the mattress frames are made. Another advantage is that, with the exception of the outer mattress cover (which may need to be formed with square rather than rounded corners) the corner blocks of the invention can be attached to the corners of the mattress frame without need of modifying the other components that cover, surround or otherwise attach to the mattress frame. A further advantage is that the corner blocks of the invention may be attached to the mattress frame at the same time that end foam padding is attached to the short ends of the mattress frame. As mentioned above, another advantage of the invention is that it may be employed with a crib mattress to decrease the likelihood that an infant lodge an extremity between a corner of the mattress and a corner of a crib frame.

FIGS. 1A-1D show various views of corner block 100 according to an illustrative embodiment of the invention. Referring to those Figures, the end block 100 includes first 102 and second 104 legs. The first leg 102 has an inner end 106 and a terminal end 108. It also has an inner surface 110 and an outer surface 112. The outer surface has first 112 a and second 112 b sections. Similarly, the second leg 104 has an inner end 114 and a terminal end 116. It also has an inner surface 118 and an outer surface 120. The outer surface has first 120 a and second 120 b sections.

The inner surfaces 110 and 118 of the first 102 and second 104 legs, respectively, intersect at a transition section 122. As depicted the transition section 122 may be curved, but this need not be the case. As shown in further detail in FIGS. 2B and 2C, the transition section 122 is sized and shaped to interfit with and cover a rounded or otherwise non-square corner of a mattress frame. In this particular embodiment, the mattress frame is a crib mattress frame. However, suitably sized and shaped corner blocks according to the invention may also be applied to any size mattress frame, for example, including single, double, full, queen, king and California king size mattress frames.

The outer surfaces 112 and 120 of the first 102 and second 104 legs, respectively, intersect at an angle to each other at a corner/vertex 124. According to the illustrative embodiment, the outer surfaces 112 and 120 of the first 102 and second 104 legs intersect at a substantially right (i.e., 90 degree) angle to form a substantially square corner 124. In the illustrative embodiment of FIG. 1, the distance 125 between the vertex 124 and an apex 123 of the curved transition section 122 is about 1 inch. However, the distance 125 may have any suitable dimension depending on the size of the particular mattress frame corner with which it is to interfit. For example, in other illustrative embodiments, the distance 125 ranges from about ½ inch to about 2 inches.

As shown in FIG. 1A, the first leg 102 of the illustrative corner block 100 has a length 126 of about 4½ inches, as measured along the outer surface 112 between the vertex 124 and the terminal end 108. However, in other illustrative embodiments, the length 126 may be any suitable length for any particular mattress frame. In some illustrative embodiments, the length 126 ranges from about 6 inches to about 12 inches. In other illustrative embodiments, the length 126 ranges from about 4 inches to about 10 inches. As also shown in FIG. 1A, the first section 112 a of the outer surface 112 extends along an axis 128 from the vertex 124. The first section 112 a of the illustrative first leg 112 has a length 130 of about 2 inches. However, it may have any suitable length depending on the particular mattress frame corner with which it is sized and shaped to interfit. In one illustrative embodiment, the length 130 is between about 1 inch and about 6 inches. In other illustrative embodiments, the length 130 ranges from about 1 inch to about 4 inches. The second section 112 b of the outer surface 112 extends from the first section 112 a. According to the illustrative embodiment, the second section 112 b extends along an axis 132 angled inward from the axis 128 of the first section 112 a. However, this need not be the case. According to the illustrative embodiment, the second section 112 b has a length 134 of about 2½ inches. However, the second section 112 b may be of any suitable length 134 depending on the particular mattress frame corner with which it is sized and shaped to interfit. In one illustrative embodiment, the length 124 ranges from about 1 inch to about 6 inches. In other illustrative embodiments, the length 124 ranges from about 1 inch to about 4 inches.

The first leg 102, in one implementation, has a width/thickness 136 of between about ¼ inch and about 4 inches. However, in other implementations, the width 136 is between about ¼ inch and about 2 inches. According to the illustrative embodiment, the angle of the axis 132 relative to the axis 128 causes the width 136 to vary from about 1 inch near the inner end 106 of the leg 102 to about ¼ inch at the terminal end 108 of the leg 102. However, in other illustrative embodiments, the axis 128 may be coaxial with the axis 132, causing the width 136 of the leg 102 to be substantially uniform along its length.

As shown most clearly in FIGS. 1B-1D, the first leg 102 has a height 138 of about 5 inches in the case of the corner block 100 being sized and shaped for interfitting with a corner of an open coil mattress frame, and a height 138 of about 4½ inches in the case of the corner block 100 being sized and shaped for interfitting with a corner of a pocketed coil mattress frame. However, as in the case of the other dimensions for the corner block 100, the height 138 may be of any suitable measurement, depending on the particular mattress frame corner with which the corner block 100 is sized and shaped to interfit. For example, in other illustrative embodiments, the height 138 is between about 3 inches and about 12 inches.

According to the illustrative embodiment, the first 102 and second 104 legs are of similar dimensions, and may or may not be symmetrical. More particularly, the second leg 104 of the illustrative corner block 100 has a length 140 of about 4½ inches, as measured along the outer surface 120 between the vertex 124 and the terminal end 116. However, in other illustrative embodiments, the length 140 may be any suitable length for any particular mattress frame. In some illustrative embodiments, the length 140 ranges from about 6 inches to about 12 inches. In other illustrative embodiments, the length 140 ranges from about 4 inches to about 10 inches. As also shown in FIG. 1A, the first section 120 a of the outer surface 120 extends along an axis 142 from the vertex 124. The first section 120 a of the illustrative first leg 120 has a length 144 of about 2 inches. However, it may have any suitable length depending on the particular mattress frame corner with which it is sized and shaped to interfit. In one illustrative embodiment, the length 144 is between about 1 inch and about 6 inches. In other illustrative ¼ embodiments, the length 144 ranges from about 1 inch to about 4 inches. The second section 120 b of the outer surface 120 extends from the first section 120 a. According to the illustrative embodiment, the second section 120 b extends along an axis 146 angled inward from the axis 142 of the first section 120 a. However, this need not be the case. According to the illustrative embodiment, the second section 120 b has a length 148 of about 2½ inches. However, the second section 120 b may be of any suitable length 148 depending on the particular mattress frame corner with which it is sized and shaped to interfit. In one illustrative embodiment, the length 148 ranges from about 1 inch to about 6 inches. In other illustrative embodiments, the length 148 ranges from about 1 inch to about 4 inches.

The second leg 104, in one implementation, has a width/thickness 150 of between about ¼ inch and about 2 inches. However, in other implementations, the width 150 is between about inch and about 2 inches. According to the illustrative embodiment, the angle of the axis 146 relative to the axis 142 causes the width 150 to vary from about 1 inch near the inner end 114 of the leg 104 to about ¼ inch at the terminal end 116 of the leg 104. However, in other illustrative embodiments, the axis 146 may be coaxial with the axis 142, causing the width 150 of the leg 104 to be substantially uniform along its length.

As shown most clearly in FIGS. 1B-1D, the second leg 104 has a height 152 of about 5 inches in the case of the corner block 100 being sized and shaped for interfitting with a corner of an open coil mattress frame, and a height 252 of about 4½ inches in the case of the corner block 100 being sized and shaped for interfitting with a corner of a pocketed coil mattress frame. However, as in the case of the other dimensions for the corner block 100, the height 152 may be of any suitable measurement, depending on the particular mattress frame corner with which the corner block 100 is sized and shaped to interfit. For example, in other illustrative embodiments, the height 152 is between about 3 inches and about 12 inches.

According to the illustrative embodiment, the inner surfaces 110 and 118 are substantially flat. However, as shown in FIG. 1D, the inner surfaces 110 and 118 may include a cutout 154 to better interfit with a corner of a mattress frame. More particularly, the cutout 154 provides an overhang 156 for extending over a top side of a corner of a mattress frame and an overhang 158 for extending over a bottom side of a corner of a mattress frame. The overhangs 156 and 158 make it easier to attach (e.g., by way of hog rings) the top and bottom of the corner block 100 to the mattress frame.

According to one illustrative embodiment, the corner block is formed from a polymer foam core. In one implementation, it has a density of about 23 kilograms/m³, and a cell size of between about ¾ millimeter and about 1¼ millimeters. However, the corner block 100 may be made from any material, including, without limitation, any suitable polymer plastic, having sufficient rigidity to maintain the squareness of the intersection 124 of the outer surfaces 112 and 120. A desirable feature of the material of the corner block 100 is also that it has sufficient shape resiliency to return to its substantially square configuration if compressed or otherwise deformed, for example, during packaging and/or shipping.

In some embodiments, the corner block 100 is formed out of a single piece of material. However, in other embodiments, the legs 102 and 104 may be attached together by any suitable mechanism.

According to another illustrative embodiment, the invention provides a mattress employing one or more corner blocks of the invention to provide substantially square corners. In other illustrative embodiments, the invention provides a method of manufacturing a mattress employing one or more corner blocks of the invention. Although an illustrative mattress and method of manufacture is described below with respect to FIGS. 2A-2I in terms of a mattress and a mattress frame, it should be noted that the corner block 100 of the invention may be sized and shaped for use with any suitable mattress and mattress frame.

Referring to FIG. 2A an end foam 200 a is attached to a short end 202 a of a coil spring mattress frame 204. In accordance with conventional practices, the attachment is by way of hog rings. As shown in FIG. 2B, a corner block 100 a of the invention is then interfitted with the corner 206 a of the coil spring frame 204, with the first leg 102 overlapping the end foam 200 and the second leg 104 extending along a portion of a long edge 208 a of the frame 204. The corner block 100 is then hog ringed in place along the top 102 a and bottom 102 b of the first leg 102 and along the top 104 a and bottom 104 b of the second leg 104. As shown in FIG. 2C, the same approach is used to attach corner blocks 100 b-100 d to each of the remaining corners 206 b-206 d and the end foam 200 b to the other short end 202 b. As also shown in FIG. 2C, the mattress frame 204 with the end foam and corner blocks attached is then placed onto a conventional synthetic fiber pad 210. As shown in FIG. 2D, the mattress frame 204 is then wrapped in the fiber pad 210 leaving the end foams 200 a and 200 b exposed. The fiber pad 210 is secured using a conventional hog ring approach. As shown in FIG. 2E, the mattress is then covered on a top surface 212 and both short ends 202 a and 202 b with a conventional upholstery 214, also secured with hog rings; leaving the long sides 208 a and 208 b and the bottom of the mattress not covered by the upholstery 214. As shown in FIG. 2F, the mattress is then wrapped in a conventional fire retardant material 216, also secured with hog rings, leaving the upholstery 214 exposed at both short ends 202 a and 202 b.

As shown in FIG. 2G, the mattress is then inserted into a polymer bag 218, which is substantially evacuated to compress the mattress. As shown in FIG. 2H, the mattress is then inserted into an outer cover 220 while in a compressed state. The compressed state enables the mattress to be easily inserted into the cover 220, without risk of ripping or otherwise damaging the cover 220. The mattress cover 220 is then closed using any suitable technique, such as stitching and/or gluing.

The evacuation bag 218 may be unsealed subsequent to inserting the mattress into the cover 220. In some embodiments, the bag 218 is unsealed and removed prior to closing the cover 220. In other embodiments, the bag 218 is unsealed prior to closing the cover 220, but left inside the cover to provide added protection for core components of the mattress, for example, against inadvertent exposure to bodily fluids during use. In further embodiments, the bag 218 is left sealed while the cover 220 is being closed and is either unsealed subsequent to closure or left to slowly inflate over time due, for example, to porosity of the bag 218 material/construction.

Turning now to FIG. 3, an alternative embodiment of the invention is depicted wherein a side piece, typically a header or footer piece, is provided that includes two corner block elements. In particular, FIG. 3 depicts a corner block 300 that includes two corner blocks 302 and 304. The corner blocks 302 and 304 are joined by a bridge 308 that connects the two corner blocks 302 and 304. Each corner block 302 and 304 includes an interior curved surface 312 and a side arm piece 310. In the embodiment depicted in FIG. 3 the corner block assembly 300 may be slide over a side of the mattress, thereby providing a corner block at two of the mattress corners. The dimensions of the corner block assembly 300 may vary according to the application, and in one embodiment the corner block assembly 300 may have dimensions suitable for allowing the corner block assembly 300 to slide over the head or foot of a mattress. However, in alternate embodiments, the corner block assembly 300 may have dimensions suitable for allowing the corner block assembly 300 to slide over the side of a mattress thereby providing a corner block at the head and the foot of the mattress. The corner block assembly 300 may be made of materials such as those used with the corner block assembly embodiments depicted in FIGS. 1 and 2. Similarly, the wall thickness and height of the corner blocks 302 and 304 may be similar to the wall thickness and height of the corner block depicted in views 1A and 1B. Optionally, the corner blocks 302 and 304, as well as the arm 308 and the side arms 310 may include a lip, similar to the lip depicted in FIG. 1D. This optional lip allows for the corner block assembly 300 to engage the upper and lower surfaces of the mattress.

Once engaged against the mattress, the mattress may be assembled as depicted in FIGS. 2A-2F and optionally be compressed as also shown in the figures.

Turning to FIG. 4, a further alternative embodiment of the corner block is depicted. In particular, a corner block assembly 320 is shown in FIG. 4 having four corner block elements 322, 324, 328 and 330. These corner block elements are joined by bridge arms 334, 338, 340 and 342. The corner blocks and the bridge arms form a peripheral sidewall having an interior cavity 332 into which a mattress may be inserted. In this embodiment, the corner bock assembly 320 provides four corner blocks that may be attached by a single assembly 320 to the mattress. Once attached, the mattress may be assembled as depicted in FIGS. 2A-2D. As described above, the corner block assemblies as well as the sidewalls 334, 338, 340 and 342 may include lip elements that butt against and optionally frictionally engage with the upper surface and lower surface of the mattress. The corner block assembly 320 may be made of the materials described above with reference to the corner block assembly shown in FIGS. 1A and B and the wall thickness and height of the corner block assembly may be similar to the wall thickness and height of the corner block illustrated in FIGS. 1A and 1B. The sidewalls 334, 338, 340 and 342 may be made of any suitable material and may have optional cutouts (not shown) within the sidewall to control stiffness of the sidewalls and to reduce the cost of materials.

It should be noted that additional modifications can be made to the illustrative embodiments without departing from the subject invention as defined by the following claims. By way of example, the corner block of the invention may be made in any suitable dimensions, from any suitable materials. Additionally, mattresses of the invention may also be of any suitable dimensions and employ any suitable mattress frame, coil spring or not, pocketed or not. Further the methods of manufacture may employ any steps including the step of locating at least one corner block of the invention in a corner of a mattress, regardless of at what point in the fabrication process the corner block is included and regardless of whether the corner block is located directly next to the mattress frame, on top of an intervening layer between the corner block and the mattress frame, covered by a subsequent layer/material or located in an exposed fashion on an outer surface of a mattress corner. Also, the corner block of the invention may or may not be affixed to the corner of the mattress or mattress frame. 

1. A corner block for squaring a corner of a mattress comprising, first and second legs each having inner and outer terminal ends, the first leg extending from an inner end of the second leg at an angle to the second leg, both legs including inner and outer surfaces, the inner surfaces of the first and second legs intersecting at a transition section, the transition section being sized and shaped for interfitting around a corner of a mattress frame, the outer surfaces of the first and second legs intersecting at a vertex of an angle, the first and second legs each having a height of between about 4 inches and about 10 inches, and a length of between about 4 inches and 10 inches measured from the vertex to the terminal end of a respective leg along the outer surface of the respective leg.
 2. The corner block of claim 1, wherein the corner block is formed from a shape resilient polymer material.
 3. The corner block of claim 1, wherein the transition section is curved to interfit around a corner of a mattress frame.
 4. The corner block of claim 1, wherein the angle is about 90 degrees.
 5. The corner block of claim 1, wherein the length is between about 4 inches and about 6 inches.
 6. The corner block of claim 1, wherein the height is between about 4 inches and about 6 inches.
 7. The corner block of claim 2, wherein the polymer material has a density of between about 18 kilograms/meter³ and about 28 kilograms/meter³.
 8. The corner block of claim 1, wherein the first and second legs are formed integrally with each other.
 9. The corner block of claim 1 having a distance from a vertex of the angle where the outer surfaces of the first and second legs intersect and an apex of the curved transition section being between about ½ inch and about 2 inches.
 10. The corner block of claim 1 having a distance from the vertex of the angle where the outer surfaces of the first and second legs intersect and an apex of the curved transition section being between about 1 inch and about 2 inches.
 11. The corner block of claim 1, wherein the first and second legs have a thickness of between about ¼ inch and about 2 inches.
 12. The corner block of claim 1, wherein the first and second legs have a thickness of between about ½ inch and about 1 inch.
 13. The corner block of claim 1, wherein the first and second legs have a thickness that decreases from the inner end of each of the legs to the terminal end of each of the legs.
 14. The corner block of claim 1, wherein the outer surfaces of the first and second legs each include first and second sections, the first section of each leg extends from the vertex at approximately a right angle to each other, and the second section of each leg extends from a terminal end of a respective first section of each leg along an axis angled inward relative to a respective axis of the respective first section.
 15. The corner block of claim 1, wherein the inner surfaces of the first and second legs includes a carved out portion sized and shaped to interfit over a corner of a mattress frame.
 16. The corner block of claim 1, wherein the block comprises a material selected from the group consisting of polyurethane, polystyrene, polymer, wood, metal, polyurethane foam, visco-elastic foam, latex, polyethylene foam, polystyrene, cardboard, cellulose, wood, wire, plastic molded part, polypropylene, and acrylonitrile butadiene styrene (ABS).
 17. A mattress comprising: a mattress frame; and at least one corner block having first and second legs each having inner and terminal ends, the first leg extending from an inner end of the second leg at an angle to the second leg, both legs including inner and outer surfaces, the inner surfaces of the first and second legs intersecting at a transition section, the transition section being sized and shaped for interfitting around a corner of the mattress frame, the outer surfaces of the first and second legs intersecting at a vertex of an angle, the first and second legs each having a height of between about 4 inches and about 10 inches, and a length of between about 4 inches and 10 inches measured from the vertex to the terminal end of a respective leg along the outer surface of the respective leg.
 18. The mattress of claim 17, wherein the corner block is formed from a shape resilient polymer material.
 19. The mattress of claim 17, wherein the transition section is curved to interfit around a corner of a mattress frame.
 20. The mattress of claim 17, wherein the corner block includes a corner block assembly having at least two corner blocks connected by a sidewall.
 21. The mattress of claim 17, wherein the mattress is a crib mattress.
 22. A method of manufacturing a mattress comprising, attaching a corner block to a curved corner of a mattress frame, the corner block being sized and shaped for interfitting around the curved corner and for transforming the curved corner into a substantially square corner, and covering the mattress including the corner block with a mattress upholstery.
 23. The method of claim 22 comprising, inserting the mattress into a polymer bag, reducing pressure in the bag sufficiently to compress the mattress, sliding a mattress cover over the mattress while the mattress is in a compressed state, and permanently closing the mattress cover.
 24. The method of claim 23 comprising, removing the polymer bag prior to permanently closing the mattress cover.
 25. The method of claim 23 comprising, leaving the polymer bag within the mattress cover.
 26. The method of claim 22, wherein attaching a corner block includes attaching a corner block assembly having a plurality of corner blocks connected by a sidewall. 